The present invention relates to strut assemblies, and more particularly, to a compression strut rod assembly used to lift a vehicle hood and to secure the hood into place in a fully opened position.
One aspect of the invention relates to a spring mechanism typically used for biasing hoods, tops, doors, hinged covers, and other elements from a closed to an opened position. The invention involves the use of springs in conjunction with a rod member to exert a driving force on the elements to be displaced. The following patents are incorporated herein by reference as background information with regard to spring mechanisms: U.S. Pat. No. 6,199,843 to DeGrace; U.S. Pat. No. 5,810,339 to Küspert, et al.; and U.S. Pat. No. 4,962,916 to Palinkas.
Compression spring rods are used in various applications; for example, to assist in lifting, opening, and damping. Typical applications include lifting a lid hinged to a stationary base. Other applications include lifting and/or balancing elements for a trunk or hood of an automobile. The present invention uses the compression spring rod assembly to assist a hood of a vehicle during opening of the hood and securing the hood in place in a fully opened position.
Gas can also be used with the strut assembly. Either gas alone or gas in combination with a spring or springs can be used to lift a vehicle hood.
Existing mechanical lifts for hoods can require greater than 100 pounds of force to open or close a hood. A strut is used to assist in over-center body locking of the hood only. Variations in handle loads occur due to variations in torsion bar forces. Since the handle loads vary, this can result in the hood falling, possibly causing an under the hood injury to a user.
Existing hood lift systems include nylon tie straps secured by brackets to the hood and radiator. Torsion bars are mounted via hood brackets and frame mounts. This can result in lateral loads on the radiator which causes related radiator stress.
Prior systems also utilize a unidirectional counter-balance which assists in opening only the hood. A variation in handle loads occurs due to a variation in torsion bar forces, resulting in increased handle loads. No device to secure the hood in an open position is present, resulting in a potential for unintended closing of the hood.
Furthermore, since there is no contact handle load, the hood can potentially free fall, resulting in possible injury to the user.
Failure of extension springs and oil dampeners in existing systems can cause greater handle loads, hard closing of the hood, and/or additional parts replacement.
In some existing systems, foiled back insulation can wear due to contact with large extension springs. A pinch point can also occur between the handle and a dampener mount, causing potential injury to the user.
Thus, there is need for a hood lift system which overcomes the above-mentioned defects and others while providing more advantageous overall results.